Tissue engineering keeps advancing.
MIT bioengineers have devised a new technique that makes it possible to learn more about how cells are organized in tissues and potentially even to regrow cells for repairing areas of the body damaged by disease, accidents or aging.
The method gives them unprecedented control over organizing cells outside the body in three dimensions, which is how they exist inside the body. It uses electricity to move cells into a desired position, followed by light to lock them into place within a gel that resembles living tissue.
Cells traditionally have been studied in two dimensions in a Petri dish, but certain cells behave differently in two dimensions than in three.
"We have shown that the behavior of cartilage cells is affected significantly when they are organized in 3-D," as is the behavior of other types of cells like stem cells, said MIT Associate Professor Sangeeta Bhatia of the Harvard-MIT Division of Health Sciences and Technology (HST), one author of a paper on the technique due to appear in the May issue of Nature Methods.
The new technique is orders of magnitude faster than previous methods used and allows very precise positioning.
The new technique allows for precise control of cell organization, and takes minutes to perform compared to hours or days for the other method.
Albrecht and his colleagues have been using a micropatterning technique to carefully position the cells within about 10 microns of each other. That's nearly the diameter of a cell and about one-fifth the diameter of a human hair. The technique uses a device made with photolithography, the same process used to create circuit patterns on electronic microchips.
In the paper, the MIT researchers said they have formed more than 20,000 cell clusters with precise sizes and shapes within a single gel. They have since scaled that up several-fold. They also have created layers of different cells, attempting to mimic the structure of tissue inside the body.
While the technique may one day be applied to engineer tissues for medical applications, its first use will be for basic research on how cells are organized, how they function and communicate in tissues, and how they develop into organs or tumors. The 3-D organization of cells also may help researchers understand how cells respond to drugs when they are in a normal state compared to a diseased state like cancer.
Cars can last much longer than their original design lives because their parts can be replaced repeatedly. Tissue engineering is really all about the development and installation of replacement parts for humans and other animals. Given sufficiently advanced tissue engineering technologies we would not need to die from age-related internal organ failure or suffer from worn out joints or tendons or ligaments. Tissue engineering advances will provide key pieces of the puzzle for how to do full body rejuvenation.